Method of making articles of polygonal cross-section



July 2, 1935. R L, WILCOX 2 006352 METHOD OF MAKING ARTICLES OF POLYGONAL CROSS SECTION Filed May 15, 1933 2 Sheets-Sheet 1 IN V EN TOR.

F/ MR0 15$ 75?ML cax.

Jufly 2, 1935. R. L. WILCQX 2,006,852

METHOD OF MAKING ARTICLES OF POLYGONAL CROSS SECT ION Filed May 15, 1935v 2 She'ets-Sheet 2 lllll Patented July 2, 1935 METHOD or MAKING ARTICLES 0F- POLYGONAL CROSS-SECTION Richard Lester signor to The Wilcox, Waterbury, Conn as- Waterbury Farrel Foundry and Machine Company, Waterbury, Conn, a corporation of Connecticut Application May 15, 1933, Serial No. 671,165

2 Claims. (01.10-27) This invention relates to new and improved means and method for making articleshaving'a polygonal cross section, particularly bolts and the like. f 7

It is the object of this invention, among other things, to produce an article of the character described by the application of successive pressures, some in the direction of the axis of the article and others at substantially a right angle therewith such-pressures resulting from the' action of mechanisms of simple design that may be adapted for use in a press, header or the like. A further object being to provide means whereby a symbol, such as a trademark or the like, may be impressed in one or more of the polygonaliaces of the article.

' To these, and other ends, this invention consists in the means and method for making articles having a polygonal cross section, having certain details of construction and combinations of parts, as will be hereinafter described and more particularly pointed out in the claims.

Referring to the drawings, wherein likecharacters of reference indicate like parts in the several figures;

Figure l is a sectional view of the applicable portion of the mechanism utilized in this invention; 1

Figure 2 is a transverse sectional view of a portion thereof, the parts in section being generally taken upon line 2-2 of Figure 1, the relative parts, however, in this view being different than in Figure 1;

Figure 3 is a fragmentary plan view of the forming die;

Figures 4, 4A, 5, 5A, 6, 6A, 6B, '1 and 7A, inclusive, are views of one form of a blank showing the shapes resulting from the several operations thereon. I

Figures 8, 8A, 9, 9A, 10, and 10A are illustrations of completed articles;

Figure 11 is a view of a blank, of slightly difierentshape, and as produced by a, pressure operation; and 7 Figure 12'is a perspective view of one of the pressure dies.

Heretofore it has been the usual practice to form the head of an" article, such as a bolt or the like, by the' application of endwise pressure upon the blank. r With this invention the polygonal shape is acquired by pressure applied to the perimeter of the head of the blank, as distinguished from endwisepressure, thereby producing a bolt head of superior quality with faces that have an attractive finish, and the metal thereof is toughened by its compression in the forming die. Thus, the product isadapted for use under more severe conditions than is possible with 7 bolt heads made under the old process. :5

In the embodiment of the invention, one form or which is illustrated in the drawings, ID designates the bed as associated with the body H, of the machine, upon which a'zdie block I2 is secured in any preferred manner. Within this latter is a cut-on die 13, pressure dies l4 and idiorming dies [6, extruding die l1, and point- Y ing die 18. The opening the cut-elf. die I3 is substantially the same shape. and size in cross section as the rod 19 from which the blanks 20 15 are cut by the knife 21. The extruding die i1 is enclosed within a die shell 22 and rests pon a backing block 23. The pointing die is enclosed within theshell 24 and upon opposite sides thereof are the guide block 25 and backing block 26. i Opposite the die holder is a punch holder 21, in which is mounted the punches 28, 29, 3| and 32, and punch carrier 30, all of which abut against a backing plate 33. In the punch carrier 25' 30 is a pressure pin 34, havingv a head thereon, and between which and'the backing plate 33 is the spring 35.

In practice the die block l2 and its associated parts are held rigid and the punch holder 21 ismoved. toward and awaytherefrom in any manner well known in the art. By reason of this motion the punches engage the blanks in'line therewith and in conjunction with (yo-operating dies and other mechanism, perform operations thereon.

When the punch holder 21 is distant from the dieblock l2, the cut-off portion of the rod (now the blank 20) is transferred intoline with the punch 28 and die Hi. The thereafter movement of the punch holder '21 toward the die block 12 causes the blankto be projected" into the-die I4 against the end of the knockout pin 36, which at this time is held in a rigid position. When-so positioned, the outer end of the blank 20' projects beyond the face of the die 14 and this portion is subjectedto the pressure of the punch 28 and is coned substantially as shown in figures l and 5. "As the punch'holder 21 moves away from the die block 12 the knockout pin' ejectsthe blank from' the die l4 and suitable transfer mechanism engages and transfers it into-line with the punch 29. Atthe next movement of the punch' holder 21 toward the die block I2, the

punch 29 engages the blank in mm therewith, 55

and projects it into the die l5 until its inner end engages the knockout pin 3'! now held in a fixed position. The action of this punch changes the shape of the coned head to one having a diameter considerably larger than that of the distance across the corners of the finished polygonal head, and considerably thinner, a collar being formed on'the inner face by the recess in the face of the die l5. With the next movement of the punch holder 2'! away from the die block I2, the knockout pin 31- ejects the blank from the die l5, which, through transfer devices is moved to the forming die I 6. The latter is constructed with a body member 38'which is held stationary within the dieljblock l2.

Through the body member is an opening 49 of plural diameters, in the walls of the smaller diameter of which are a plurality of radial slots 4|. The rear walls of these slots (six in number) are at an angle to the axis of the opening 40, and as the'apparatus is shown, arerdesigned to producean article that is hexagonalincross. section. A-g reater'-or less number. of faces will correspondingly increase or reduce the number of slots. Movable in each-slot. is. a pressure die 42 which has afiat inner face 43 of .substantially the width ofleachof the faces .of the polygonal head, and each ofvthe faces. being. substantially parallel with the faces of .the other pressure dies 42 in the groups Oneach die opposite its pressure .face is cam' face 44, which rides against the a gular-wail ofLtheslotsAl, an inner cam face and a stop shoulder 46.

Moyablymountedwithin the opening 40 and a concentric opening in the bushing 47 is a sleeve 48 having a coned head 49, the angle of inclination of which is substantially the same as that of thecam faces 45, which engage therewith. Surrounding thesleeve 48 and between a :collaniflthereon land the bushing 41, is a coil spring 5|, which maintains a constant tension ,uponihesleeveito move it toward the exposed :faceof thedie block. 7 .Secured to the body member 38 is a plate 52 againstrwhichthe stop shoulders 46 engage when ,the'pressure dies, 42. are in their outer position, :that :is,...hreferably withthe ends thereof sub stantially flush with the exposed face of the die block [2.1

1-; Withinthe sleeve 48 is aguide sleeve 53 having a stopnshoulder 54,.which engages a shoulder :within thebore of the sleeve .43 and limits the relative 1 movement. thereof .in one direction. This; position, being shown and illustrated in figure 2, wherein thexface of, this guide sleeve is substantially flush with the exposed face of the .die.bl0ck.12;.. Surrounding the sleeve 53 within the bore. ofjthe. sleeve 48 and between the shoulder 5.4 anda" nut L55,sis a spring 55 that is much lighterthan,thezspring 5|. Movable within the .nut. 55. and sleeve 53, is a knockout pin 51.

' In Figure. 2 the several parts constituting the 1f0rming..dies, the ..punch carrier 30, and asso- .ciated parts arein their relative positions as. the blankispresented ,thereto'andstill held by the transfer devices. W V

\ As, the punch holder 2.! moves toward the die bloclg,l 2,.theblank is pushed into the sleeve 53 by the; pressure pin '34 and, the underside of the ,head; thereof engages; the end of said sleeve. Further continued, movement compresses the relatively light spring .55 until the, inner end of the sleeye;,53 abuts against the nut 55,.at which time theopposite end of the sleeve is substantially fiush with-the face of the coned head 49 substantially as shown in Figure l. The head of the blank is now positioned between the pressure faces of the dies 42, and the spring is compressed during the further movement of the punch carrier until the end of the latter engages the outer faces of the die 42. Thereafter, continued movement of the punch carrier 38 imparts movement to the pressure dies 42. These dies under this action move inwardly toward the axis of the blank by reason of the engagement of the cam faces 44 with the walls of the angular radial slots 4|. Endwise pressure is also thus applied to the sleeve 48 through the engagement of' the cam faces 45 with the coned head 49. During the inward movement of these dies 42, the inner pressure faces 43 are forced against the outer wall of the head of the blank, causing the metal to flow by reason of such pressure until the inward limit of movement of the dies 42 is reached, that is, until the angular walls on. each side of the pressurev faces contact with each other, thus completely shaping the head.

As pressure is applied by the dies 42.and the metal flows as a result thereof, both in an up and a down direction, this flow is not resisted to any appreciable extent. This results from the receding of, the pressure pin 34 into the punch carrier 30, and the free space above the coned head. Such space is provided through the engagement of the cam faces 45 with the coned head 49 which moves the. sleeve away from the head of the blank against the tension of the spring 5i faster than the metal flows. As the punch carrier 30 is withdrawn the spring 5| forces the sleeve 48 outwardly, thus moving the pressure dies away from the axis of the blank and out of engagement with the head thereof. At the same time the knockout pin 51 projects the blank out of the guide sleeve 53 which moves outwardly relatively to the sleeve 48 by the tension of the spring 56. When the guide sleeve 53 is in its outer position, determined by the engagement of the collar 50 with the body member, the outer end of the guide sleeve 53 is flush with the exposed face of the die block i2. The transfer mechanism now engages the blank and carries it to the extruding die I! where it is projected therein by means of the punch 3i, after which it is ejected by the knockout pin 59 and presented to the pointing die !8, being projected therein by the punch 31?. and ejected therefrom by the knockout pin 58. If the underside of the head is slightly irregular by reason of the application of the pressure dies 42 thereto, this irregularity is eliminated and the face made flat in the next succeeding operation in the extruding die H, as shown. This results, within the die, from the endwise pressure applied to the head, which will eliminate any irregularities therein.

The inner sleeve 53 provides a convenient means for receiving and guiding the blank into the forming die. It is particularly advantageous for blanks with short shanksbecause the outer end thereof is flush with the exposed face of the die block 12, while theconed head 49 is distant therefrom, the open space between the coned head and face of the die block being bridged by the sleeve 53. Thus, there is produced by the means and mechanism described and disclosed, a bolt blank that is produced from a wire rod and the head shaped by lateral pressure, the shank extruded and pointed if desired; The lateral pressure applied by this process produces the polygonal shaped head without the application of subsequent endwise pressure, as where the head is preliminarily fluted by lateral or other means.

With some metals the extent of irregularity on the top and bottom faces of the head is greater than in others and this tendency may be materially counteracted by forming the underside of the head with irregularities, the high points of which will correspond with the natural flow of the metal in the succeeding operation where the tendency to irregularities would be the least and vice versa. To accomplish this, the die I5 is preferably provided with a face that is formed with depressions, substantially as shown at in Figure 6, separated by intermediate high points 6 I. In Figure 11 is shown a die and blank so formed and as presented to the forming dies. The positions of these high points. 6| such that they are substantially opposite the corners of the. polygon where there is less tendency to lengthwise flow than at the centers of the flat faces, which are opposite the These depressions are entirely depressions 6|. removed in subsequent endwise pressure operations and the metal at the bottom thereof is caused to flow so that it is substantially flush with the high points 62, thus producing a flat as distinguished from an irregular surface.

It is desirable in some cases that articles of the character herein referred to should be identified by a symbol, trade-mark or the like, whereby to indicate when and by whom manufactured, or to indicate the character of the material of which the article is made, and for other reasons. Attempts have been made to accomplish this result, by forming the symbol on the top face of the article. This is unsightly and destroys its neat appearance, and if the symbol is raised rather than impressed, it is further objectionable, because it forms an obstruction upon which cloth, waste, or the like, will catch and cling when the articles and adjacent parts are being cleaned. Again in the manufacture of have been utilized in the process of manufacture to indicate the character of the material of which the article is made. In such cases, these symbols are removed before the article is finished, so that the means of identification are thereafter lost. In this invention the heretofore mentioned objections, and others, are eliminated, and all of the advantages of a symbol or trademark are preserved. This is accomplished by providing the pressure face of one or more of the dies 42 with an impression face 39, shown in Figure 12 as diamond shaped. Obviously any such articles, symbols or marks,

other design may be used equally as well, 'the shape disclosed being merely for the purpose of illustration. The impression face 39 leaves a corresponding permanent impression in the flat face of the article as the die 42 is withdrawn therefrom. This result is accomplished without the aid or addition of additional parts or operations. An impression upon a side face of the article, as produced in this invention, is not unsightly and does not destroy the neat and pleasing appearance of the article. Neither does 7 it interfere with the grip of the article by a wrench or the like.

The above disclosure is given merely as'one embodiment of the present invention, which is not to be considered as limiting the invention, the scope thereof being determined by an understanding of the present disclosure as one embodiment thereof and as particularly pointed out in the appended claims. 7 I

What I claim is:

1. The method of making by a cold process articles having a polygonal cross section, which resides in, shaping a substantially cylindrical blank so that at one end it will have a substantially domed surface of solid cylindrical cross section throughout and then applying axial pressure to one end face only thereof, whereby the height of the blank is reduced and the cylindrical cross sectional area thereof increased to a size that is greater in diameter than the. distance across the corners of the finished polygonal article, and then applying pressure around the perimeter thereof, whereby the height of the blank is increased and its then cylindrical cross sectional area reduced and made polygonal in form.

2. The method of making by a cold process articleshaving a polygonal cross section, which resides in shaping a substantially cylindrical blank so that at one end it will havefa substantially domed surface of solid cylindrical cylindrical cross sectional area reducedand made polygonal in form, and one or more of the sides of the polygon provided with a distinctive symbol, trade-mark, or the like.

RICHARD LESTER. WILCOX. 

